


Resonance

by SirLadySketch



Category: Kingdom Hearts
Genre: Demyx the idiot, Gen, Science, Studying the heart, Zemyx if you squint, the nature of the heart and what it remembers, zexion the scientist
Language: English
Status: Completed
Published: 2020-04-28
Updated: 2020-04-28
Packaged: 2021-03-02 02:26:48
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,267
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23897485
Author URL: https://archiveofourown.org/users/SirLadySketch/pseuds/SirLadySketch
Summary: Zexion has work to do, but his latest test subject seems to have a mind of its own, and Demyx isn't helping.Short oneshot set sometime between the events of BBS and Days with zemyx vibes, but can be interpreted as gen, too.
Comments: 6
Kudos: 8





	Resonance

The heart is a fickle thing.

This particular specimen seems exceptionally sensitive, pulsing and twitching within its chamber, the glow rising and fading with every beat. It’s relatively large -- probably came from an adult victim, maybe someone from the castle itself -- but it flutters in the chamber like a little bird, trembling and fluctuating to a pattern of its own making. The way it sways within its tank is like a slow dance, a gentle rocking to a song only it can perceive.

Zexion makes a note of the odd behavior as it idles between tests. There hasn’t been anything out of the ordinary in its reactions to his previous experiments, and all the measurements fall within typical parameters. But left to its own devices, this heart has its own life, or at least, some sort of spiritual memory imprinted upon it. Its previous owner must have been someone special.

But there’s no music here in the labs. The only sound he notes is an odd hum that rises just above the sound of the machines; a higher, wavering pitch that dips and rises with the false heartbeat of his research equipment, and for a moment, Zexion wonders if things need recalibrating. He’s been at this test for hours, after all, and it’s possible that running the numbers too long has overheated the system. 

He reaches out to fine-tune some of the settings when he realizes there are interruptions in the sound, and he pauses in his note taking to count the time between each gap. It’s rhythmic, but intermittent, and in focusing his attention upon it he realizes that there’s a quick, rasping sound after each pause. 

He closes his eyes to concentrate, to count the pauses between the beats, trying to determine if there’s a pattern to the dissonance in an otherwise optimal setup.

“You ok there, dude?”

The humming is gone. Zexion looks up from his equipment to focus on the interruption, and sees Demyx waving at him over one of the monitors. He hadn’t heard the man approach, too caught up in his research. He cannot fathom _why_ Demyx would come down here, either. They’re not particularly close, although Demyx is always friendly to anyone not asking him to do work. The Melodious Nocturne grins, seeing he’s caught his attention at last, and gestures to the room.

“You were just, like, staring off into space. Have you gone outside today?”

Zexion frowns. 

“I have work,” he says. It’s not a concise answer to the question though, so he adds, “No.”

“Figured as much.” Demyx flops down onto Vexen’s empty chair, stretching his hands over his head to crack his spine before lounging back in such a way that’s bound to cause further muscle spasms. Zexion wonders if he should advise Demyx as such, but the man doesn’t seem to notice the awkward position. Instead, he rolls up to the tank and taps on the glass, and the heart within gives a sympathetic pulse with each beat. Zexion makes a note of the reaction.

Demyx takes the opportunity to wheel around the open space, going from machine to machine, peering at screens and looking at the readouts. Zexion cannot figure out what it is he hopes to accomplish, but keeps a careful eye on the buttons and dials-- Demyx has a tendency to _meddle_.

“I still have work,” he says after a moment when it’s apparent that the musician doesn’t plan to leave. This earns him a grin as Demyx rolls across the room again.

“Don’t mind me, pretend I’m not even here!”

“You shouldn’t be here,” Zexion says, then gestures to the equipment and his current subject. “I need to conduct these experiments in a controlled environment. The Superior is expecting results.”

“He’s not coming down, is he?” Demyx asks, suddenly on edge of his seat. Zexion peers at him, curious, and makes a mental note of the reaction.

“I’ll be delivering a report when the research has been completed,” he says, and the response is instant. Demyx sprawls back in his chair with a relieved smile and summons his sitar.

“Sweet! Yeah, then, don’t mind me, imma just hang out down here for a bit,” he says, and plucks out a few notes on his instrument.

Zexion studies him, unsure of what to do. By all accounts he outranks Demyx and should just order him out. He has work to do, after all, and it’s clear that Demyx is looking for a place to hide from his own chores. The equipment is sensitive and the Superior was quite clear that he wanted results asap. If Vexen were here, Demyx wouldn’t have dared to venture into the lab in the first place, but his mentor is briefing Xemnas and will be gone for some time. In fact, it’s likely that Vexen will not return for the evening, since he’ll need to collect the field research from Saïx. 

Against his better judgement, he shrugs, and turns back to his work.

True to his promise, Demyx keeps relatively quiet-- for him, at least. He’s still humming under his breath, tapping his foot on the floor as he ghosts fingers over his sitar strings and bridges. There’s a whisper of a song there, but it’s soft enough that the machinery doesn’t seem to pick up any of the vibrations

The heart, as always, is a fickle thing.

Zexion resumes the calibrations, and while the readings show little change, there is a visible reaction within the heart chamber itself. It pulses in sympathy to the tapping of Demyx’s foot, swaying and brightening as Demyx hums out snatches of a song. 

Curious, Zexion reaches back and puts a hand on Demyx’s knee, stilling the man instantly. The heart stops as well, fading back to its pale pink glow and soft, listless beat. Then Zexion gestures for Demyx to play again, and the heart beats bright and happy, startling a laugh out of the musician.

“Aww, the little dude likes my music! Must’ve been a music aficionado before kicking the bucket.”

Demyx begins to play in earnest, fingers dancing up and down the neck of his instrument as the heart dances with him. Zexion mulls that over. It’s something to consider, certainly. While they have no way to directly trace the heart’s origin, what he _can_ do is see if there are other stimuli that have a similar impact.

He tries to type out his notes as quietly as possible so as not to disturb this moment, but Zexion wishes he had some sort of way to visually record this. There’s a clear and distinct action-reaction going on, and while it’s not something they’re actually testing, he has no doubt that both Vexen and the Superior will be interested. He may be able to requisite Demyx’s services for further testing, to see if the heart is simply responding to a new face, or if the music is the attraction. Would different music change the reactions? Would Demyx be amenable?

His fingers pause at that. It’s one thing to suggest a new way to study the heart, but doing so will require him to explain how he came up with the idea. Admitting the truth would implicate both of them-- Demyx for shirking his duties, and Zexion for letting him do it. 

Still, he thinks this is definitely a thread they should pursue. If a heart retains some of its personality from when it was human, is there a way to communicate with it? Is the reaction the result of residual emotions housed within the heart itself, or does the heart _itself_ react? The implications of the latter could suggest sentience, which could mean the possibility of communication at some point. He’s loathe to risk pursuing something that could assist in the reconstruction of Kingdom Hearts, even at the risk of chastisement.

He returns his attention to Demyx and watches him with a thought to take further notes, but he pauses, unable to focus on the keys under his fingers. Demyx and the heart are lost to the song -- a pretty melody, Zexion hadn’t noticed until now -- the long, plaintive notes hanging in the air. The hum of the machinery provides a droning note, and the heart’s pulse skips around in a bright, enthusiastic chirp. 

He’s not a musician, but Zexion can tell that the song means something to the other man. Demyx is somewhere else, lost in his memories, perhaps, eyes closed and his whole body swaying with the song. He cradles his sitar in his arms in a lover’s embrace, cheek against its neck, lips forming words that don’t quite make it out. Zexion has never seen him like this before, so confident, so sure of himself. This Demyx looks almost human, and, not for the first time, he wonders who this man had been in his past life.

All too soon the song comes to an end and he realizes he’s forgotten to make observations and take notes. Perhaps it’s for the best. It’s too intimate a scene to try to distill into clinical data. Watching Demyx breathe in, breathe out, open his eyes-- and the spell is broken as Demyx laughs and reaches over to tap the heart chamber. The heart flitters about a few more pulses of light before returning to its regular stasis.

“Guess he liked that, huh?” Demyx asks and Zexion nods, tilting his head to observe him.

“I will need to report this,” he says at last, and almost feels guilty when he sees Demyx’s crestfallen face, quickly replaced by one of unease. Zexion picks up his notes and skims what he’s written. There will need to be a few adjustments, of course, and he’ll need to make sure that he records things properly in the future, but everything should be in order. He looks up and gives Demyx a small, secretive smile.

“The heart responded to all normal tests in the standard way, but the introduction of music to the tests caused an immediate and repeatable reaction,” he says, and hums a few lines of the song Demyx had played. The heart responds at once, its gentle pulse brightening for the few refrains before falling back into its sleep. Zexion makes another note of this before continuing.

“The subject responded to a short song, hummed by myself, and reacted for the full duration of a song. This shows a new level of emotional response previously unrecorded, and it is my suggestion that we pursue this study further. I will request the assistance of the Organization’s musician to see if different instruments and types of songs have more significant responses, and determine further actions we may take, contingent on test results.” He pauses and lifts his pencil from the notepad. “ _Would_ you be willing to assist in this? It may require many weeks of study.”

Demyx grins and gives him a thumbs up, dismissing his instrument as he stands.

“What, and miss out on getting chased by angry heartless, or getting reamed out by Saïx for shoddy paperwork? I owe you one, so yeah, of course I’d help!” He turns and taps on the glass a few times. “This lil’ dude and I are gonna science _so hard_ together! Oh--” he grinned at Zexion--”I guess it’ll actually be the three of us, huh?”

“I’ll be observing, not participating,” Zexion says, already thinking through the tests and studies they could try. 

If they could requisition more hearts, they could test things out in batches, see if there was an effect diminished by distance, or if there would be a measurable variance depending on the individual. He itches to get started now, but there is too much to do, too much to set up. He’ll have to write up a short presentation and get it to the Superior and Vexen before it’s too late, which means he’ll have to hurry. He gives Demyx another small smile.

“I need to finish the paperwork before the others retire for the evening, but I have no doubt that you’ll be hearing something in the next day or two.” Demyx nods, clearly expecting it. “I doubt the request will be refused. I look forward to working with you.”

Demyx grins and bounces to his feet, fist bumping Zexion’s hand still holding the pencil. “It’s gonna be awesome!” he agrees, then opens a dark corridor, no doubt off to officially clock out for the day. He gives Zexion a finger salute before ducking inside. “Later dude!”

Zexion realizes several minutes later that he’s still smiling as he typed up the report, adding in his hypothesis and suggested course of actions. Odd. He doesn’t smile that often, hadn’t done so even when he was human. He wonders if it was a lingering effect of the song, some residual resonance or influence from the heart. He looks back at it but there is no reaction, no indication of the earlier activity.

Interesting. He gets to his feet and finishes collecting his notes from the printer, then straightens his coat. He finds himself hoping that Xemnas will immediately approve of this project and allow him to bring Demyx down into the labs with him, perhaps as early as tomorrow. A little unorthodox, perhaps, but he hadn’t realized how much he’d enjoyed the other man’s company until he realized he was excited to see him again. To try new experiments, to hear new songs, to see more of this unfamiliar side of his comrade.

The heart is a fickle thing, he knows, and he can’t wait to learn more of its secrets. 


End file.
